In recent years, as a packaging material configured to pack a viscous product such as cheese portion having a small block shape, which may enter a fluidic state, a set of a sheet material having tear tape (tear strip) attached thereto has been widely used. The packaging material is configured such that, in a state in which the viscous product is packed, when the tear tape is pulled, the sheet material is torn to expose the viscous product to the outside.
Such kinds of packaging materials, for example, are provided in the following patent documents 1 to 3.    [Patent Document 1] Published Japanese translation of a PCT application, No. 2006-508868    [Patent Document 2] Japanese Utility Model Publication No. H01-26623    [Patent Document 3] Japanese Patent Application, First Publication No. S62-168869